Antennas used in radio equipment are required to be small size and a high sensitivity. In order to reduce the size of an antenna, a line width needs to be narrower. When a wiring material such as copper, gold and silver is used, a high frequency antenna in particular has a long wiring length, and for this reason, the loss caused by the wiring is high, and the antenna efficiency is reduced. On the other hand, when the size of area of an antenna is reduced, the gain of the antenna is likely to decrease.